The present invention relates to digital image processing systems and, more particularly, to a signal processing system for improving the resolution by mean of compensating the contour of luminance and chrominance signals and extending their horizontal frequency bandwidth.
In conventional digital image processing systems using a standard signal, the frequency band of a luminance signal is 4.2 MHz, while those of chrominance signals R-Y and B-Y are 1.3 and 0.5 MHz, respectively. The luminance signal is added to an original signal after compensation of its horizontal-contour and the chrominance signals are band-amplified and next demodulated, where band-amplification gain is determined by an automatic chrominance gain controller, depending on the demodulated chrominance signals. The processed luminance and chrominance signals are mixed again at a matrix part and next displayed on a screen.
With low frequency bands of image signals, however, high frequency components are not processed sufficiently due to the difference of transition times resulting from the level difference, thereby degrading the resolution.